1. Field of the Invention
The present invention relates to an apparatus for cooling media sheets in a printer, the apparatus comprising: a number of cooling units; a conveyor having a first conveyor path adapted to feed the media sheets successively through the number of cooling units; and a switch adapted to deflect selected ones of the media sheets into a second conveyor path, wherein the switch is disposed upstream of a last one of the number of cooling units and downstream of a first one of the number of cooling units, and the second conveyor path bypasses the last one of the number of cooling units.
2. Description of Background Art
In a printer such as a laser printer or an ink jet printer, the media sheets are frequently subjected to processing steps, e.g. a step of fusing a toner image or a step of drying ink, which results in the sheets being heated to an elevated temperature, so that it is necessary to cool them down again after the print process.
There are several ways to cool the sheets. For example, the sheets may be moved along a cooled stationary part or they may be pressed against a surface of a co-moving member, e.g. a rotating drum having a metal surface with high heat conductivity. The drum may be provided with internal cooling fins or the like for transferring the heat withdrawn from the media sheets onto a cooling medium such as a liquid or ambient air or cooled air. In any case, the necessary measures for cooling the sheets add to the total energy consumption of the printer.
U.S. Application Publication No. 2014/0029995 A1 describes a cooling apparatus in which the sheets are successively passed over peripheral surfaces of two cooling drums.
In some printers, a switch is provided in the conveyor path for diverting selected ones of the media sheets to a different destination. For example, in a duplex printer, some sheets are to be directed to a discharge tray whereas other sheets are to be re-circulated in a duplex path of the printer.
JP 2009-237514 A discloses an apparatus for cooling media sheets in a printer.